A communications network such as a telephone network, has become more than a facility for merely permitting two geographically remote customers to engage in private conversation. Many special services are now being offered such as audio conferencing, video conferencing, credit card calling and special billing, etc. While these services can be provided through the use of an attendant, it is more desirable to fully automate these services without attendant intervention.
These special services, however, require the customer to perform tasks not normally encountered in the average station to station call. For example, the customer may be required to dial a special series of digits to initiate the call and then send additional digits during the call to cause other action to take place.
An example of this might be in the establishment of a conference call whereby the caller dials a code to access the conference circuit and then dials another code to add a conferee or to subtract a conferee from the conference call.
To advise a customer of the necessary procedures for making these calls, it is desirable to give the customer instructions over the telephone at the time action has to be taken. Thus, if a customer makes a mistake in dialing, a new instruction can be automatically given to prompt the customer to correct the mistake. Likewise, if alternative services are available, the customer can be informed automatically of what the alternative services are and what action must be taken to implement each service.
Providing a multiplicity of announcements in real time requires a large capacity store that can be rapidly accessed so as not to keep customers waiting.
One such arrangement is disclosed in the copending U.S. patent application of T. W. Anderson et al., U.S. Ser. No. 232,999, filed Feb. 9, 1981 now U.S. Pat. No. 4,357,493. In the Anderson et al. disclosure, complete announcements are stored on a rotating disc store having multiple reading heads. Each announcement is repeated in a plurality of locations on the discs and these locations are arranged in staggered relationship to each other so that in real time one of the reading heads is always near the beginning phrase of one copy of the announcement. The discs are continuously read so that each copy is loaded into a corresponding playback buffer. Thus, selection of a buffer assures prompt access to the beginning of an announcement.
While the Anderson et al. arrangement is suitable for its intended purpose, it requires that several copies of each announcement be stored, and this uses valuable storage capacity which is undesirable when a large repetoire of high quality speech must be stored. Also, all announcements must be fully assembled before they are entered in the store, and the arrangement does not lend itself to assembling in real time, unique announcements from a plurality of short phrases which may be common to many announcements. Thus, the average waiting time for an announcement with the staggered disc arrangement is unacceptably long for the present application.